The only thing I would change is the doors... To me it feels like they get in the way more than anything else. A neat work around might have been to have more traditionally styled (for doom) door stuck in the up position. As if they were permanently opened due to a puzzle solved elsewhere. (I'm thinking of Doom 2's Tricks and Traps). You'd still have the appearance of divided sections and door ways for the sake of keeping the look, but without having to actually battle the doors. Edited 27.3 minutes after the original posting.
Oh golly, this takes me back... but yes, I have always tried to keep a consistent tone, to evoke a sense of place in time with my maps. I'm entirely happy if it's "too Doomish" - that was kind of the point. (Hence the blue key, BTW)
I have noticed your maps are very simple and you use the same texture for one particular map you make. I actually think this map is good but next time try to experiment with more textures. I feel like this map is created from a Doom game.
